People on Twitter collectively fact-checked President Donald Trump after he incorrectly claimed during his border visit Thursday that wheels are older than walls.

“They say ‘a wall is medieval.’ Well, so is a wheel. A wheel is older than a wall. And I looked, and every single car out there — even the really expensive ones the Secret Service uses — [and] I said, ‘Do they all have wheels?’” Trump joked during his visit to the U.S. border pic.twitter.com/4GxiQVzOlT

Trump made the bizarre statement during his trip to the U.S.-Mexico border arguing for funding to build his promised wall. Here’s what Trump said:

“They say a wall is medieval, well so is a wheel. A wheel is older than a wall. And I looked at every single car out there, even the really expensive ones that the Secret Service uses, and believe me they are expensive. I said, do they all have wheels? Yes. Oh, I thought it was medieval. The wheel is older than the wall, you know that? And there are some things that work. You know what? A wheel works and a wall works.”

And here’s how people on Trump’s favorite social media platform responded:

Trump in McAllen, Texas: "Many are saying that on the third day, God created Wall. And, you know, it worked. And it still works. So he did wheel, you know, soon after. Great wheels. But walls came first. Big walls from God. Good ones. Mine will be better, but His were good."

I fully expect him to one day say: “Imagine if the wall had wheels. It would be a wheeled wall. A hot, wheeled wall. Hot Wheels. Remember those? A lot of people don’t know Hot Wheels aren’t full size. They’re more like really small cars. Nobody knows Hot Wheels better than me.” https://t.co/tjcpgwjnLA

I’d just like to say that rocks are older than both walls and wheels and have been used as tools—great tools!—for a longer than the dinosaurs have been around. And that means the rocks probably killed the dinosaurs! Sad! But rocks are used in walls, so we must have rocks!!